The map definition file contains a list of CRSs, not included in epsg.db.
The file name is mapdef.dat and it is located in the system folder (for example, C:\Program Files\CARIS\Caris\<version>\system).
Do not edit default file. Create a copy of this file and use the copy for custom map definitions. |
International foot = 0.3048m |
US survey foot = 0.30480061m (1200/3937 per US SPCS 1927) |
Lines that start with # are comments.
Map definition entries are collected in groups. The group name, enclosed in square brackets, is on a line by itself, followed by an unlimited number of definitions, one per row. Each definition can be no longer than 400 characters.
Definition fields are separated by commas. The first five fields are required. The remaining fields (the numeric fields) depend on the CRS and projection. If a numeric field is not required, enter a value of 0. You cannot leave a field out.
Each definition line has the following format:
Field | Type | Maximum | Description | Example |
Key | Char | 20 chars | The map definition key. Must be unique. |
|
Description | Char | 80 chars | A description for the definition. Must be enclosed in double quotes. Must contain no commas. |
|
Coordinate system | Char | 4 chars | NEMR or LLDG |
|
Ellipsoid | Char | 4 chars | From the datum file. See Datum File |
|
Projection | Char | 4 chars | Projection code. See the list below. |
|
Scaling latitude 1 | Real | 10 dec. places | The latitude of the geographic origin. |
|
Scaling latitude 2 | Real | 10 dec. places | The latitude of the geographic origin |
|
False North | Real | 10 dec. places | An offset applied to all northing. |
|
False East | Real | 10 dec. places | An offset applied to all eastings. |
|
Scaling factor | Real | 10 dec. places | The amount of distortion to be expected at the geographic origin. |
|
Latitude origin | Real | 10 dec. places | The latitude of the geographic origin. |
|
CMorLO | Real | 10 dec. places | Central meridian or longitude origin, depending on the projection. |
|
Skew azimuth | Real | 10 dec. places | The azimuth of a great circle which passes through a point of origin. |
|
CARIS uses four horizontal coordinate systems:
Coordinate System | Description |
NEMR | The coordinates are expressed as Northings and Eastings of a projection in metres on the ground (hence Northings and Eastings in MetRes). Distances and bearings can be carried across adjacent map sheets with this coordinate system, meaning that a continuous database can be established. Its application includes the atlas grid and is used primarily in land-based applications. |
NRMR | Coordinates expressed in metres on the map have no reference to a specific location on the ground (hence Non Registered, MetRes). This type of coordinate system is used when a map needs to be created for demonstration purposes only where the information necessary for relating the map to the real world (control points) is not necessary. |
LLDG | Coordinates are expressed in latitude and longitude in decimal degrees on a reference ellipsoid (hence Latitude and Longitude in Decimal deGrees). Data may be digitized in Latitude and Longitude by typing the coordinates or by batching a number of measurements and applying them at one time. Another method of obtaining data is to digitize in another coordinate system and then convert to LLDG. |
CHMR | Coordinates are expressed in metres at the chart scale (hence CHart in MetRes). All distances and bearings are relative to that chart. Thus a stored position near the top right-hand corner of the physical map would be similar to the actual map dimensions. This stored position can nevertheless be transformed to Northings and Eastings or geographic latitude and longitude as required. This coordinate system is used primarily for hydrographic charting. |
Valid CARIS projections:
Projection | EPSG Projection Definition | Code |
Alaska Zone 11 | A1 OBLIQUE MERCATOR VARIANTA ("EPSG", "9812") | A1 |
Ablers Equal Area | ALBERS EQUAL AREA ("EPSG", "9822") | AE |
Azimuthal | AZIMUTHAL EQUIDISTANT ("EPSG", "9832") | AZ |
Cassini | CASSINI SOLDNER ("EPSG", "9806") | CA |
Gauss-Krueger | TRANSVERSE MERCATOR ("EPSG", "9807") | GK |
Gnomonic | OBLIQUE AND_EQUATORIAL STEREOGRAPHIC ("EPSG", "9809") | GN |
Google Mercator | PSEUDO MERCATOR ("EPSG", "1024") | GM |
Hotine Oblique Merc A | OBLIQUE MERCATOR VARIANTA ("EPSG", "9812") | HB |
Hotin Oblique Merc B | OBLIQUE_MERCATOR_VARIANTB("EPSG", "9815") | OM |
Lambert Conformal Conic | LAMBERT CONIC CONFORMAL_2SP ("EPSG", "9802") | LC |
Mercator | MERCATOR VARIANTA ("EPSG", "9804") | ME |
Mercator | MERCATOR VARIANTB ("EPSG", "9805") | MR |
Polyconic | AMERICAN POLYCONIC ( "EPSG", "9818") | PO |
Polar Stereographic | POLAR STEREOGRAPHIC VARIANTA ("EPSG", "9810") | PS |
Rectified Skew Orthomorphic | No EPSG reference | RS |
Stereographic | OBLIQUE AND EQUATORIAL STEREOGRAPHIC ("EPSG", "9809") | ST |
Transverse Mercator | TRANSVERSE MERCATOR ("EPSG", "9807") | TM |
Universal Transverse Mercator | TRANSVERSE MERCATOR ("EPSG", "9807") | UM |
1 A1 is a special projection with all hard-coded values
Note that three projections in epsg.db have no corresponding two-character codes and thus are not included in mapdef.dat:
• CYLINDRICAL EQUIDISTANT ("EPSG", "1028")
• LAMBERT CONIC CONFORMAL 1SP ("EPSG", "9801")
• LAMBERT AZIMUTHAL EQUAL AREA ("EPSG", "9820")
Projection |
Alaska Zone 11 |
Alaska Conformal |
Albers Equal Area |
Azimuthal |
Cassini |
Equid. Conic A |
Equid. Conic B |
Equirectangular |
Gauss-Krueger |
Gnomonic |
Hammer |
Hotin Oblique Merc B |
Interrupted Goode |
Interrupt Mollweide |
Lambert Azimuthal |
Lambert Conformal Conic |
Miller Cylindrical |
Mercator |
Mollweide |
Orthographic |
Polyconic |
Polar Stereographic |
Robinson |
Rectified Skew Orthomorphic |
State Plane |
Stereographic |
Sinusoidal |
Transverse Mercator |
Universal Transverse Mercator |
Van der Grinten |
Wagner IV |
Wagner VII |
1 A1 is a special projection with all hard-coded values
When creating a new entry, the numeric fields you have to consider depend upon the coordinate system and projection.
Fields | Projections | |||||||||||
CA | GK | GN | HB | LC | ME | PO | PS | RS | ST | TM | UM | |
Scaling lat 1 | NEMR CHMR |
CHMR | NEMR CHMR | NEMR CHMR | NEMR CHMR | NEMR CHMR | NEMR CHMR | NEMR CHMR | NEMR CHMR | NEMR CHMR | NEMR CHMR |
CHMR |
Scaling lat 2 |
|
|
|
| NEMR CHMR | NEMR |
|
|
|
|
|
|
False northing | NEMR |
| NEMR | NEMR | NEMR | NEMR |
| NEMR | NEMR | NEMR | NEMR |
|
False easting | NEMR |
| NEMR | NEMR | NEMR | NEMR |
| NEMR | NEMR | NEMR | NEMR |
|
Scaling factor | NEMR CHMR |
| NEMR | NEMR | NEMR CHMR |
|
CHMR | NEMR CHMR | NEMR CHMR | NEMR CHMR | NEMR CHMR |
|
Latitude origin | LLDG | LLDG | LLDG | LLDG | LLDG | LLDG | LLDG | LLDG | LLDG | LLDG | LLDG | LLDG |
Central meridian/longitude origin | NEMR LLDG CHMR |
LLDG CHMR | NEMR LLDG CHMR | NEMR LLDG CHMR | NEMR LLDG CHMR | NEMR LLDG CHMR | NEMR LLDG CHMR | NEMR LLDG CHMR | NEMR LLDG CHMR | NEMR LLDG CHMR | NEMR LLDG CHMR |
LLDG CHMR |
Skew azimuth |
|
|
|
|
CHMR |
|
|
| NEMR CHMR |
|
|
|
Fields that do contain a marker may require a value, depending on the definition. If it turns out that a particular field is not required, it should contain a 0 in the map definition entry.
NEMR
In the NEMR coordinate system, the coordinates are expressed as Northings and Eastings of a projection in metres on the ground. Distances and bearings can be carried across adjacent map sheets with this coordinate system.
This table shows which fields you may require for a map definition using the NEMR coordinate system. Any field with no marker is not required and should contain a 0.
Field | Projection | |||||||||||||
A1 | AZ | CA | GK | GN | HB | LC | ME | P0 | PS | RS | ST | TM | UM | |
Scaling latitude 1 | * | l | l | l | l | l | l | l | l | l | l | |||
Scaling latitude 2 | l | l | ||||||||||||
False northing | | l | l | l | l | l | l | l | l | l | ||||
False easting | | l | l | l | l | l | l | l | l | l | ||||
Scaling factor | | l | l | l | l | l | l | l | l | |||||
Latitude origin | * | |||||||||||||
Central meridian/longitude origin | | l | l | l | l | l | l | l | l | l | l | |||
Skew azimuth | | l | ||||||||||||
* For the A1 projection, you must include the same value in both scaling latitude 1 and latitude origin.
LLDG
In the LLDG coordinate system, coordinates are expressed in latitude and longitude in decimal degrees on a reference ellipsoid.
CHMR
In the CHMR coordinate system, Coordinates are expressed in metres at the chart scale. All distances and bearings are relative to that chart.
This table shows which fields you may require for a map definition using the CHMR coordinate system.
Field | Projection | ||||||||||||
AZ | CA | GK | GN | HB | LC | ME | P0 | PS | RS | ST | TM | UM | |
Scaling lat 1 | l | l | l | l | l | l | l | l | l | l | l | l | |
Scaling lat 2 | l | ||||||||||||
False northing | |||||||||||||
False easting | |||||||||||||
Scaling factor | l | l | l | l | l | l | l | ||||||
Latitude origin | |||||||||||||
Central meridian/longitude origin | l | l | l | l | l | l | l | l | l | l | l | l | |
Skew azimuth | l | l | |||||||||||
Samples
Sample entries from the map definition file:
[UTM - NAD83] |
UTM-24N-Nad83,"Zone 24N (42 W TO 36 W)",NEMR,NA83,UM,0,0,0,500000,0.9996,0,-39,0 |
UTM-25N-Nad83,"Zone 25N (36 W TO 30 W)",NEMR,NA83,UM,0,0,0,500000,0.9996,0,-33,0 |
UTM-26N-Nad83,"Zone 26N (30 W TO 24 W)",NEMR,NA83,UM,0,0,0,500000,0.9996,0,-27,0 |
UTM-27N-Nad83,"Zone 27N (24 W TO 18 W)",NEMR,NA83,UM,0,0,0,500000,0.9996,0,-21,0 |